High voltage miniature relay



y 1966 v. E. DE LUCIA ETAL 3,250,886

HIGH VOLTAGE MINIATURE RELAY Filed Nov. 2'7, 1964 fur/7611207 far flaw/760 a z z z a Ar 3,250,886 HIGH VOLTAGE MINIATURE RELAY Victor E. DeLucia, Santa Monica, and Clilford A. Le

Beau, Los Angeles, Calif., assignors to Torr Laboratories, Inc., LosAngeles, Calif., a corporation of California Filed Nov. 27, 1964, Ser.No. 414,329

7 Claims. (Cl. 200-166) The present invention relates to relays ingeneral, and it relates to high voltage relays in particular, forexample, of the double-pole, double-throw type, which are United StatesPatent particularly adapted to high voltage, medical uses and a whichare constructed to assure that under no conditions will one contact openwithout the other.

In heart defribrillator systems, a double-pole, doublethrow relay isused to introduce a high voltage to the heart of the patient underprecisely controlled conditions. The relay is required to operate underhigh Voltage conditions to that vacuum relays are well suited for thepurpose. This is because vacuum relays operate in an evacuated envelope,so that contact deterioration is inhibited to a material extent.However, pressurized relays, in which the envelope is filled with apressurized dielectric gas, such as sulphurhexafiuoride (SP are alsosuited. This is because the gas reduces ionizing elfects in the envelopeand also provides a cooling effect.

In heart defribrillator systems, it is most important that both of thenormally-closed contacts of the relay open when the relay is energizedand that both of the normally-open contacts open when the relay isde-energized. If in either instance, should one contact open without theother, the results are usually fatal to the patient.

The improved relay of the present invention is particularly constructedto operate over extended intervals of time at extremely high voltages,To this end, the relay is constructed to minimize arcing. In addition,appropriate shielding is provided to shield sensitive components of therelay from ion currents produced by the high voltages involved.

In addition, the improved relay of the invention is constructed so thatif one of the normally-closed contacts should stick in a closedcondition, neither of the two normally closed contacts will open whenthe relay is energized.

Conversely, should either of the normally open contacts stick in aclosed condition, neither will open when the relay is de-energized. Thislatter factor is realized by providing fixed contacts which areresilient in one direction so as to prevent contact bounce when they areclosed; but which are rigid in the other direction so as to prevent anymovement of the movable contact away from either of the fixed contacts,should either of the fixed contacts become welded, or otherwise stuck,to the movable contact.

- This latter feature of the invention assures that when the relayis'energized and tie-energized, in each instance, either both contactsopen or neither will open. This obviates any tendency for high voltagesto be introduced to the patient under other but controlled conditions.

The features and advantages of the invention will become apparent from aconsideration of the following description, when the description isconsidered in conjunction with the accompanying drawing, in which:

FIGURE 1 is a perspective view, partially in section, illustrating avacuum relay constructed in accordance with one embodiment of theinvention;

' FIGURE 2 is a cross-sectional view essentially along the line 22 ofFIGURE 1; and

FIGURE 3 is a fragmentary view of certain operating components of therelay of the invention, with certain of the components repositioned forpurposes of clarity.

The vacuum relay illustrated in the drawing includes an envelope 10which may be formed of glass, or other suitable vitreous material. Theenvelope 10 has a generally cylindrical form in the illustratedembodiment, and it has an open portion at its lower end. The envelopemay be evacuated, or filled with gas-as mentioned above.

The open portion of the envelope is enclosed by a circular cup-shapedmember 12, which is composed of iron or other magnetic material. Thecup-shaped member includes an elongated integral cylindrical portion 13,and a plunger 14 (composed of iron or other magnetic material) issupported in the cylindrical portion 13 for reciprocal movement therein.The plunger 14 includes a'flat disc-like top 14a, and it serves as thearmature for the relay.

A suitable energizing coil assembly 16 is mounted externally of theenvelope 10 in position to surround the cylindrical portion 13 of thecup-shaped member 12. A coil spring 18 is mounted on the plunger 14between its cup-shaped top portion and the top surface of the cup-likemember 12.

The assembly is such that when the energizing coil 16 is energized, theplunger 14, which is composed of magnetic material, is drawn down intothe cylindrical portion 13. On the other hand, when the coil isdeenergized, the plunger is returned to its upper position, illustratedin FIGURE 1, by the spring 18.

A pair of electrically conductive contact pins 20 and 22 are mounted onthe envelope 10 and extend into the envelope as shown in FIGURES l and2. A corresponding pair of movable contacts 24 and 26 are hinged to therespective contact pins 20 and 22.

As mentioned previously, the relay of the invention is intended tooperate on a double-pole, double-throw basis, and in conjunction withextremely high voltages. For that reason, it is most important thatarcing be prevented.

In order to prevent arcing, a positive hinge assembly is provided forcoupling the movable contacts 24 and 26 to the respective contact pins20 and 22. This hinge assembly, as best shown in FIGURE 3, for example,takes the form of a pair of resilient strips composed, for example, oftungsten, indicated 30 and 32.

The strips 30 and 32 are welded, or otherwise affixed, to the contactpin 20 in facing, parallel relationship. A pair of channel-formingmembers composed, for ex ample, of molybdenum, and designated 34 and 36,are respectively aflixed to the remote ends of the strips 30 and 32. Thelatter two members define a transverse channel with respect to the strip30 and 32, and this channel resiliently receives a transverse rod 38, soas to permit angular movement of the rod between the two channel-formingmembers 34 and 36. The rod 36 is welded, or otherwise aflixed to themovable contact 24 in transverse relationship therewith. In assemblingthe relay, the movable contact 24 has its transverse rod 38 snapped intoplace between the channel-forming members 34 and 36.

A similar hinge assembly is used to couple the movable contact 26 to thecontact pin 22.

A U-shaped member 4% is mounted on the top surface of the disc-likeportion 14a of the armature plunger 14, and the U-shaped member hasupwardly extending legs. These legs are coupled to the movable contacts24 and 26 through insulating glass portions 42 and 44 these portionsbeing shielded against ion attack by respective shields 46 and 48. Theglass portions are attached to further elongated members 50 and 52 whichare pivoted to the respective movable contacts 24 and 26, as shown.Alternatively, the movable contacts may be supported on the armature byelongated insulating rods composed, for example, of an insulatingmaterial such as sapphire, which is immune to ion attack and does notrequire shielding.

An L-shaped shield 54 is supported on the movable contact 24, and asimilar shield 56 is supported on the movable contact 26. These shieldsserve to prevent the flow ionizing current to the elongated members 50and 52, so as to obviate any flow of current through the respectivepivot points of the movable contacts, with resulting degradation of thepivoted joints.

-It will be appreciated that when the relay is ,deenergized, the movablecontacts 24 and 26 are moved by the spring 18 to an upper position, asshown in FIGURES l and 3. On the other hand, when the relay isenergized, both the movable contacts are pulled to a lower position asthe armature 14 is retracted down into the energizing coil 16.

During this actuation of the relay, the movable contacts 24 and 26 pivotsmoothly in the corresponding hinge means, such as the hinge describedabove, so that positive electric contacts between the movable contactsand the pins 20 and 22 is assured, and arcing is prevented.

The relay illustrated in the drawing is a double-pole V double-throwrelay and is intended primarily to be used for medical purposes.However, it should be evident that the relay of the invention may besingle-pole single-throw, single-pole double-throw, double-polesingle-throw, or

other type, and that it finds general utility in many applications wherehigh voltage relays are required.

The illustrated relay includes a further pair of contact pins 60 and 62which extend through the envelope and which support corresponding fixedcontacts. These contacts are the normally-open contacts of the relay,and are engaged by the respective movable contacts 24 and 26 when therelay is energized. The relay also includes a further pair of contactpins 64 and 66. These latter contact pins constitute the normally-closedfixed contacts of the relay, and are engaged by the respective movablecontacts 24- and Zdwhen the relay is de-energized.

The normally-open contacts may each have the configuration shown inFIGURES l and 3, with respect, for example, to the pin 60. As shown, thefixed contact associated with that pin includes a rigid elongatedportion 60a, and a resilient strip portion 60b. The resilient stripportion overlies the rigid portion, and is affixed to the rigid portionat one end, for example, by a weld 60c. The resilient portion extendsbeyond the end of the rigid portion, and a contact button 60d is afiixedto the extremity of the resilient portion, which is in position to beengaged by a corresponding contact button on the movable contact 24. 7

Likewise, the normally-closed fixed contacts associated with the contactpins 64 and 66 may each have the construction shown, with respect to thefixed contact associated with the pin 64, in FIGURE 3.

The latter contact has an elongated rigid portion 64a, and an overlyingresilient strip portion 64. The strip portion is welded at one end tothe rigid portion, as by a weld 64c. As before, the resilient portion641; extends beyond the end of the rigid portion 64a, and it has acontact button 64d which is engaged by acorresponding contact button onthe movable contact 2411.

It will be appreciated that when the movable contact 24 closes with thecontact button 69d, the resilient strip 6% is caused to move away fromthe rigid portion 60a, so that the engagement by the movable contact 24is resiliently absorbed and contact bounce is prevented. However, whenthe movable contact'breaks with the fixed contact, the rigid portion 60aprevents any follo wing of the movable contact by the contact button60d. The same vent any tendency for a fixed contact to move with themovable contact.

Therefore, in the event that a fixed contact should become welded with amovable contact, its inherent rigidity prevents the armature from movingso that the corresponding contact on the other side of the relay is alsoheld closed. In this manner, there is no tendency for one half of therelay to operate, without the other.

Also, due to the high voltages with which the relay is to be operated,arcing is a problem. This arcing is prevented by the improved hingemeans of the movable contacts 24- and 26, as described above. Inaddition, the shields 54 and 56 and 42 and 44 prevent ionizing currentsfrom flowing to the critical parts of the relay.

In addition, adisc-like shield is mounted on the disc-like portion 14aof the armature 14 by means, for example, of a pair of legs 82 and 84.The disc 80 may be composed, for example, of glass, and the legs 82 and84- may be fused in the glass and welded on the surface of the disc-likemember 14a. The disc 80 is intended to prevent the flow of ionizingcurrent between one half of the double-pole double-throw relay and theother.

The invention provides, therefore, an improved vacuum relay whichisparticularly adapted to operate with high eflic-iency in switchinghigh voltages, and to operate for long periods of time withoutappreciable deterioration of its components.

While a particular embodiment of the invention has been shown anddescribed, modifications may be made. The claims are intended to coverthe modifications which fall within the scope of the invention.

What is claimed is:

1, A relay including: an envelope; a first electrically conductivecontact pin extending into said envelope; a movable contact; a pair ofspaced parallel resilient electrically conductive strips atfixed to saidfirst contact pin;

' a pair of transverse channel-forming electrically conductive membersrespectively afiixed to the ends of said strips in mutually facingrelationship; an. electrically conductive transverse rod afiixed to saidmovable cont-act and resiliently received in the channel formed by saidchannel forming members for angular movement therein; a secondelectrically conductive contact pin extending into said envelope; and afixed contact affixed to said second contact pin in position to beselectively engaged by said movable contact.

2. The relay defined in claim 1 in which said resilient strips areformed of tungsten and in which said transverse channel-forming membersand said transverse rod are formed of molybdenum.

3. A double-pole double-throw relay including: an envelope; a first pairof electrically conductive contact pins extending into said envelope; apair of movable contacts; hinge means for coupling each of said movablecontacts to a corresponding one of said pins of said first pair inelectrically conductive relationship therewith, each of said hinge meanscomprising a pair of spaced parallel resilient electrically conductivestrips affixed to the corresponding one of said contact pins of saidfirst pair, a pair of electrically conductive transverse channel-formingmembers respectively afiixed to the ends of said strips in mutual facingrelationship, and a transverse rod of electrically conductive materialaflixed to the corresponding one of said pair of movable contacts andresiliently received in the channel formed by said channel-formingmembers for angular'movement therein;.a second pair of electricallyconductive contact pins extending into said envelope; and a pair offixed contacts affixed to respective ones of said contact pins of saidsecond pair in position to be selectively engaged by corresponding onesof said movable contacts, each of said fixed contacts having a rigidportion and further having a resilient strip-like portion overlying saidrigid portion on the side thereof remote from said movable contact andextending beyond the extremity of said rigid portion to be selectivelyengaged by said movable contact.

4. A relay including: an envelope; a first electrically conductivecontact pin extending into said envelope; a

movable contact; hinge means for coupling said movable contact to saidfirst pin in electrically conductive relationship therewith; said hingemeans comprising a pair of spaced parallel resilient electricallyconductive strips affixed to said first contact pin, a pair oftransverse channelforming electrically conductive members respectivelyaffixed to the ends of said strips in mutually facing relationship, andan electrically conductive transverse rod afiixed to said movablecontact and resiliently received in the channel formed by saidchannel-forming members for angular movement therein; a secondelectrically conductive contact pin extending into said envelope; afixed contact aflixed to said second contact pin in position to beselectively engaged by said movable contact, said fixed contact having arigid portion and further having a resilient strip-like portionoverlying said rigid portion on the side thereof remote from saidmovable contact and extending beyond the extremity of said rigid portionto be selectively engaged by said movable contact.

5. A double-pole double-throw relay including: an envelope; a first pairof electrically conductive contact pins extending into said envelope; apair of movable contacts; hinge means for coupling each of said movablecontacts to a corresponding one of said electrically conductive pins ofsaid first pair in respective electrical conductive relationshiptherewith, each of said hinge means comprising a pair of spaced parallelresilient electrically conductive strips afiixed to the correspondingcontact pin of the first pair, a pair of transverse channel-formingelectrically conductive members respectively afiixed to the ends of saidstrips, and a transverse rod of electrically conductive material afiixedto such movable contact and resiliently received in the channel formedby such channel-forming members for angular movement therein; a secondpair of electrically conductive contact pins extending into saidenvelope; and a pair of fixed contacts afiixed to respective ones ofsaid contact pins of said second pair in position to be selectivelyengaged by corresponding ones of said movable contacts, each of saidfixed contacts having a rigid portion and further having a resilientstrip-like portion overlying said rigid portion on the side thereofremote from the corresponding one of said movable contacts and extendingbeyond the extremity of said rigid portion to be selectively engaged bysuch movable contact.

6. A relay including: a first electrically conductive terminal means;means including a pair of spaced parallel resilient electricallyconductive strips connected to said terminal means and defining atransverse channel at the end of said strips; means including a movablecontact having an electrically conductive transverse rod resilientlyreceived in said transverse channel for angular movement therein; asecond electrically conductive means; and a fixed contact electricallyconnected to said second electrically conductive terminal means andpositioned to be selectively engaged by said movable contact.

7. A relay including: an envelopeya first electrically conductiveterminal means extending into said envelope; means including a pair ofspaced parallel resilient electrically conductive strips connected tosaid terminal means and defining a transverse channel at the end of saidstrips; means including a movable contact having an electricallyconductive transverse rod resiliently received in said transversechannel for angular movement therein; a second electrically conductiveterminal means extending into said envelope; and a fixed contactelectrically connected to said second electrically conductive terminalmeans and positioned in said envelope to be selectively engaged by saidmovable contact.

References Cited by the Examiner UNITED STATES PATENTS 1,821,813 9/1931Nickle 200-l44.2 X 2,794,885 6/1957 Jennings 200144.2 3,161,749 12/1964Perry et al. .4 ZOO-144.2

BERNARD A. GILHEANY, Primary Examiner. I. J. BAKER, Assistant Examiner.

1. A RELAY INCLUDING: AN ENVELOPE; A FIRST ELECTRICALLY CONDUCTIVECONTACT PIN EXTENDING INTO SAID ENVELOPE; A MOVABLE CONTACT; A PAIR OFSPACED PARALLEL RESILIENT ELECTRICALLY CONDUCTIVE STRIPS AFFIXED TO SAIDFIRST CONTACT PIN; A PAIR OF TRANSVERSE CHANNEL-FORMING ELECTRICALLYCONDUCTIVE MEMBERS RESPECTIVELY AFFIXED TO THE ENDS OF SAID STRIPS INMUTUALL FACING RELATIONSHIP; AN ELECTRICALLY CONDUCTIVE TRANSVERSE RODAFFIXED TO SAID MOVABLE CONTACT AND RESILIENTLY RECEIVED IN THE CHANNELFORMED BY SAID CHANNELFORMING MEMBERS FOR ANGULAR MOVEMENT THEREIN; ASECOND ELECTRICALLY CONDUCTIVE CONTACT PIN EXTENDING INTO SAID ENVELOPE;AND A FIXED CONTACT AFFIXED TO SAID SECOND CONTACT PIN IN POSITION TO BESELECTIVELY ENGAGED BY SAID MOVABLE CONTACT.